Re: Back branches vs. gcc 4.8.0

On 2013-04-05 23:28:03 +0100, Peter Geoghegan wrote:
> On Fri, Apr 5, 2013 at 11:14 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > It also strikes me that we ought to take this as a warning sign
> > that we need to work on getting rid of coding like the above in favor
> > of genuine "flexible arrays", before the gcc boys think of some other
> > overly-cute optimization based on the assumption that an array declared
> > with a fixed size really is fixed.
>
> The traditional argument against that has been that that's a C99
> feature. However, since it appears that even MSVC supports flexible
> arrays (which are described as a "Microsoft extension", so may not
> have identical semantics), it might be possible to do this across the
> board without contorting the code with preprocessor hacks. That's
> something that I'd certainly be in favor of pursuing.

The respective macro magic is already in place, its just not used in all
places. The problem is more that we can't easily use it in all places
because e.g. in the one case mentioned here the array isn't in the last
place *in the back branches*.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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